Problem: What is the greatest common factor of $24$ and $28$ ? Another way to say this is: $\operatorname{gcf}(24, 28) = {?}$
Answer: The greatest common factor is the largest number that is a factor of both $24$ and $28$ The factors of $24$ are $1$ $2$ $3$ $4$ $6$ $8$ $12$ , and $24$ The factors of $28$ are $1$ $2$ $4$ $7$ $14$ , and $28$ Thus, the greatest common factor of $24$ and $28$ is $4$. $\operatorname{gcf}(24, 28) = 4$